Boot issue, won't post... sometimes

I've been messing around with this issue for weeks and haven't had much luck. Hopefully people might have some ideas.

A few months back my computer was off when I went downstairs in the morning. Probably a power failure. When I turned my system on the computer wouldn't post.

So, I pulled all my ram and cleaned my system. I reinstalled the ram and it still wouldn't work. I proceeded to start testing 1 ram stick at a time. Any 2 ram would work at the same time so I conceeded to work with a 2gig in my first slot and a 1 gig in my 3rd slot (the pair slot for slot 1). This worked for a few weeks and than one morning my computer wouldn't post at all.

So here I am now.
Today I completely stripped my system down and rebuilt. I added a new power source just as a suspicion and proceeded to try. Nothing, no post. I pulled all ram and put my 2gig in ram slot 1. No Post, I placed 1gig in slot 1 and it posted and gave me a Checksum error. Probably because I had pulled my battery a week or so ago. I defaulted in the bios and rebooted. Load took it to the "Windows did not load properly" and I chose start windows normaly. At this point I get the first windows loading bar and than black and nothing. The CD rom spools up like a mad beast for about 3 mins and than everything calms and nothing more occurs.

Today since getting it to post the screen has also had small horizontal lines (green and red) forming vertical bars down the screen of the monitor. Not sure what thats about.

So, I dont know if its the ram since 1 stick works and another wont. Although none will result in a full boot so that leads me to think mobo ram slots rather than the ram itself.

What suggestions would anyone have. At this point im thinking mobo is the problem, but I can't be sure.

My appologies if this is the wrong forum for this issue, im new to the board.

After testing the ram extensively I discovered my 2gig is fryed. So, once I was aware of that I proceeded to boot the computer and got all sorts of crazy lines on my screen and a boot failure at the point where windows should launch.

Videocard seemed to be the problem. (8800 GTS) I went through some diagnostics came to the conclusion that my video card was, in fact, shot. So, as a last ditch effort I dismantled the old girl (8800 gts) completely, and hucked her in the oven at 385 degrees for 9 minutes, mmm, mmm, golden brown.

Needless to say, it worked. I've never felt so powerful when fixing a computer as I do right now. Imagine that, cooking a video card. LOL. Good ole soder and its low melting point.

Thanks a ton for pointing out the potential of multipul broken peices. I was approaching my problem without perspective for so long it never occured to me.